0.7 Music, biological evolution, and the brain

Abstract

This essay offers a novel theoretical perspective on the evolution of music. At present, a number of adaptationist theories posit that the human capacity for music is a product of natural selection, reflecting the survival value of musical behaviors in our species’ past (e.g., Wallin et al., 2000). In sharp contrast, a prominent nonadaptationist theory of music argues that music is a human invention and is biologically useless (Pinker, 1997). I argue that research on music and the brain supports neither of these views. Contrary to adaptationist theories, neuroscientific research suggests that the existence of music can be explained without invoking any evolutionary-based brain specialization for musical abilities. And contrary to Pinker’s claim, neuroscience research suggests that music can be biologically powerful. By biologically powerful, I mean that musical behaviors (e.g., playing, listening) can have lasting effects on nonmusical brain functions, such as language and attention, within individual lifetimes. Music is thus theorized to be a biologically powerful human invention, or “transformative technology of the mind.”

1. introduction

The past decade has witnessed a rapid rise in cognitive and neuroscientific research on music. This has led to renewed interest in evolutionary questions about music, which originate with Darwin’s discussion of the topic in The Descent of Man (1871). There are now several adaptationist theories arguing that musical behaviors originated via biological evolution due to their survival value for human ancestors. In contrast, nonadaptationist theories propose that musical behaviors are a human invention. The most prominent such theory, that of Steven Pinker (1997), regards music as a pleasure technology built from pre-existing brain functions (such as language, emotional vocalization, etc.), and posits, “As far as biological cause and effect are concerned, music is useless” (p. 528).

Pinker’s idea that music is an invention built from existing brain functions provides a useful null hypothesis for evolutionary debates over music. His assertion that music is biologically useless, however, is problematic. While Pinker was likely referring to music’s impact on human biology over evolutionary time, as opposed to within the lifetime of individual humans, his writing does not make this distinction. Furthermore, the metaphors he uses to describe music (e.g., “auditory cheesecake,” or “recreational drugs”) imply a view of music as having little biological significance at either evolutionary or individual timescales. While Pinker’s (1997) characterization of music as auditory cheesecake seemed to trivialize music, in more recent writings he has been more careful about assessing the value of music in human cultural life, noting, “The arts could be evolutionary by-products, and be among the most valuable human activities for all that” (Pinker, 2007, p. 170).

A central point of this essay is that discussions of the biological significance of music should conceptually distinguish music’s effects over evolutionary time from its effects within individual lifetimes. The need for this distinction is driven by evidence from neuroscience. Neuroscientific research suggests that music is an invention that builds on diverse, pre-existing brain functions, rather than a trait that originated via processes of natural selection. This is consistent with Pinker’s thesis. However, growing evidence from neuroscience also suggests that music is biologically powerful, meaning that it can have lasting effects on nonmusical abilities (such as language or attention) during the lifetime of individual humans. Importantly, these effects can be observed not only in trained musicians but also in ordinary individuals who engage regularly with music. Thus, I believe that music should be regarded as a biologically powerful human invention or “transformative technology of the mind.” (For brevity, henceforth I refer to this idea as TTM theory.)